1. Field of the Invention
The present invention relates to a switch used to operate electronic equipment.
2. Description of Related Art
With recent advances in the compact and low-profile design of various kinds of electronic equipment such as the TV set, video recorder, air conditioner or the like, the switch used for the equipment is also required to be compact, low-profile, and reliable.
Such a conventional switch is described with reference to FIGS. 4 and 5. FIG. 4 shows a perspective view of the conventional switch and FIG. 5 shows a cross-sectional view of the same. In FIGS. 4 and 5, generally box shaped case 1 is formed from an insulation resin and is open-topped. Fixed contact 2 is formed from a conductive thin metal plate. A plurality of fixed contacts 2 are securely implanted on internal surfaces of case 1, with terminal pins 2A protruding downward from the bottom surface of case 1.
Operating body 3 is formed from an insulation resin and is housed in case 1 and is vertically moveable. Head 3A protruding upward is formed on top of operating body 3.
Movable contact 4, which is formed of an elastic thin metal plate bent into an open sided square, is mounted on operating body 3. Movable contact 4 touches fixed contact 2 elastically to form a switch assembly.
Cover 5 is formed from an insulation resin and spring 6 has a coiled form. Cover 5 covers an opening in the top surface of case 1 and spring 6 is mounted between the bottom end of operating body 3 and the internal bottom surface of case 1 while being compressed slightly. Spring 6 biases operating body 3 with head 3A protruding upward out of the opening in the top surface of case 1.
Cover 5 is provided with a pair of supports 5A extending downward. Land 1A disposed on a side surface of case 1 catches groove 5B of support 5A to fix cover 5 on case 1.
A certain number of switches thus formed are stored or transported in packed in a bag and then head 3A is provided with a push-button before the switch is built into an operation panel of electronic equipment. Terminal pin 2A of fixed contact 2 is connected electrically to a circuit of electronic equipment by soldering or the like.
When head 3A provided with push-button or the like is pressed in the above configuration, operating body 3 moves downward while compressing spring 6. With the movement, fixed contacts 2 to which movable contact 4 touches elastically are switched over, performing an electrical switching.
When head 3A is released from the pressing force, operating body 3 returns upward to the original position by the restoring force of spring 6.
Japanese Patent Unexamined Publication No. 2004-273199 is known as an example of the above-described conventional switch.
However, when stored, packed in bags and transported, or built into equipment, the aforementioned conventional switches have collided with each other or with tools or the like, occasionally hitting support 5A of cover 5. Upon such an outward force being applied to support 5A, groove 5B would come off from land 1A provided on the side surface of case 1, causing problems such as breakdown or unreliable operation of the switch.